Adjustable speed-starting device for electric motors and the like



e. 0.. W ILMS. ADJUSTABLE SPEED STARTING DEVICE FORVELECTRIC MOTORS AND THE LIKE.

' APPLICATION FILED MAY-T2, 1920.

2 sHEETs-sH EET 1.

Patented 0@t.10,1922.

- e.- 0. WILMS. ADJUSTABLE SPEED STARTING DEVICE FOR ELECTRIC MOTORS AND THE LIKE.

APPLICATI'ON FILED MAYI2,19'20.-

1,431, 4 Patented Oct. 10,1922

2 SHEETSSIHEET 2.

LINE

mam A7 64141321211: 0- M7716.

Patented Oct. 10, 1922.

UNITED STATEs PT'ENT OFFICE GUSTAV O. WILMS, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO THE RELIANCE COM- PANY, OF MILWAUKEE, "WISCONSIN, A CORPORATION OF WISCONSIN.

ADJUSTABLE SPEED-STABTING DEVICE FOR ELECTRIC MOTORS ANT) THE LIKE.

Application filed May 12,

To all whom it may concern:

Be it known that I, GUs'rAv O. Wit-Ms, a citizen of the United States, and resident of Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Adjustable Speed-Starting Devices for Electric Motors and the like; and I do hereby declare that the following is a full, clear, and exact description thereot.

My invention relates to new and useful improvements in current controlling devices more particularly of that type wherein variation of the current is procured by compression of. a resistance medium interposed in the circuit, the present device being of that general type shown in Patent No. 992294, issued to G. C. Thompson, May 16, 1911, and adapted for starting the operation of a motor.

It is primarily an object of my invention to provide an arrangement wherein the compressible resistance medium of the control device is utilized to procure a ready variation of the flow of current upon completion of the motor star-ting, cycle of operation of the control device, in addition to the normal function of said resistance medium for varying the flow ofcurrent incidental to said starting cycle of operation.

It is further my object to'provide an arrangement whereby the control device may be adjustably set at any time for a desired rate of current flow, whereby in the instance of motor operation, the speed of the motor being varied by manipulation of the control device durin the operation of the motor and independently of the starting mechanism.

It is a still further object of my invention to improve the general structural arrangement of devices of this character and to provide an improved housing for the various working parts of the device.

With the above and other objects and advantages in view, my invention resides more particularly in the novel combination, formation and arrangement of parts hereinafter described and pointed out in the appended claims.

In the accompanying drawings Figure 1 is a vertical sectional view through a. current controlling device embodying, my invention, the plane of this 1920. "swarm. 380,759.

" igure 2- is a transverse sectional view on the line 22 of Fig. 1;

Figure 3 is a detail sectional view of the i switch mechanism of the device, the plane of this section being indicated by the line 3-3 of Fig. 2; V Figure 4 is a diagram of the wiring arrangement employed in the present device, .Reterring now more particularly to the accompanying drawings, I provide in the present embodiment of my device a casing including the walls 5, top 6 and bottom 7. Transverse upper and lower partitions 8 and 9 respectively,are disposed within the casing and each partition carries an insulating slab 10. The resistance units of the device are of the usual carbon pile type, each unit comprising'a tube 11 in which is mounted a pile of carbon disks 12 The end portions of the tubes fit snugly within openings in the insulating slabs 10, the partition 1 plates 8 being provided with registering relatively larger openings, and studs'13 project from the tops of the tubes to receive pressure "for compressing the disks, the tubes being held against longitudinal movement by lateral projections on their upper end portions above the upper slab 10, the projections being formed by screw-heads 14 in the 5 present instance. Fo compressing the disks in the current-varying cycle of operation of the device, and also independently of said cycle of operation, a transverse shaft 15 is journaled in the casing and carries .outwardly thereof an operating crank-handle '16, a cam disk 17 being fixed on the shalt within the casing and carrying a cam-ring 18 confined between a pair of circular plates 19 secured to the disk. A tension-rod 20 is secured to and extends upwardly from the ring 18,'said rod passing through the upper partition and through the base of a cupshaped depression 21 formed in the intermediate portion of a pressure-distributing plate 22 which is adapted to engage the pressure studs 13 of the resistance columns, A handwheel 23 is threaded on the upper end of.

the rod 20, which projects through the casing top 6 and this hand-wheel has a relatlvely long depending hub sleeve portion which abuts a cap member 24 slidable on the rod engaging a relatively strong spring 25 handle 16 is swung coiled on the ,rod within the depression 21 of theplate, this spring serving to impart an even tension to the pressure-distributing plate incidental to movement of the tensionrod 20 or incidental to movement of the hand-wheel 23 on the rod. A pair of posts 26 rise from the upper insulating slab l0 and are loosely passed through openings in the pressure-distributing plate 22, these posts ser'vingto hold the plate against rotation and having springs 27 coiled thereon and engaging the plate to raise the same from the studs 13 when tension is relieved from the rod 20. The rod 20 is raised in tension-relieving position when the crankdownwardly, abutting a suitable stop-mem member is swung upwardly, however, tension is imparted by the downward cam-impelled movement of the rod throughthe spring 25 to the pressure-distributing plate 22, whereby an even pressure is exerted on all of the resistance columns, this pressure gradually increasing as the handle is swung upwardly to its desired limit;

Rotation of the shaft 15 also serves to make and break the circuit ofthe resistance columns, and thus a contact head 29 is se cured on the shaft adjacent, the wall of the casing and carries a pair of .arcuate contacts 30 having their ends spaced a art to define gaps at diametrically oppose portions of the contact head. A pair of spring-urged contact arms 31 are secured on an insulating slab 32 carried by the casing wall and each of these arms carries a finger 33 extended toward the contact head, the extremity of each finger being bent outwardly of the head to provide a proper contact surface for en agement with a corresponding contact 30.

he arms 31 are connected by suitable flexible contacts 34 with binding posts 35 from which the proper circuit connections are made, When the crank-handle is in lowered pressure-relieving position, the contact fingers 33 are disposed at the gaps of the rotatable contact'head, and as the shaft 15 is rotated to compress the columns, the fingers engage and ride upon the arcuate contacts 30, being maintained in contact at the' upper limit of movement of the crankarm. The. device is automatically locked in this position by a pivoted latch-hook 36 adapted to engage a pin 36 carried by the contact head 29, one end of said hook 36 being extended to form' an armature for co-operation with a coil 37 energized by closing the maincircuit whereby a drop of current in the main circuit will release the device and open the main circuit, the shaft 15 rotating under influence of a spring 38 wound thereon and having its ends engaged against pins 39 and 40 carried respectively by the casing and by a crank projection of, the shaft.

er 28. When the handle sure is gradually supplie Taking up now the wiring arrangement employed in the use of the present device as a motor-starter, and referring particularly to Fig. 4, 41 designates one of the main supply circuit wires which is connected with the armature 42 of the motor controlled by the device. The other line wire 43 is connected with one of the contact fingers 33 and current is adapted to pass therefrom through the arcuate contacts 30 to the other'pivotal contact 33 from whence a line 44 extendsv to the resistance columns, which are connected in series with each other and connected by wire 45 with the other side of the motor armature. The circuit 46 for the shunt field 47 of the motor includes the hold ing magnet 37.

hus, taking up the operation of the present device, it will be seen that upward swinging movement of the handle 16, rocking the shaft 15 will first close the contacts 30 and 33, and the current flowing through the main circuit described will be slight in view of the high. resistance of the carbon columns by reason of their freedom from pressure. As the handle 16 is swun upwardly, presto the columns, as is common to controllers of this character and the current is gradually increased in accordance with the development of the motor speed, and at the full limit of upward movement of the crank-handle, a certain normal running speed will be imparted to the motor and the mechanism will be held in this position by the armature hook 36 under influence of the magnet 37. When it. is desired to vary the normal running speed of the motor, the hand-wheel 23 is rotated in either direction to increase or lessen the speed by applying greater pressure or by relieving pressure with respect to the resistance columns and this adjustment is effected independentl of the starting action for the motor, uti izing however the starting resistance columns 12 as a means for efi'ecting this normal speed variation.

1 am aware that controlling devices of this general character have been heretofore provided wherein the effective length of the tension rod for the resistance column or columns has been adjustable by reason of abutment nuts threaded thereon, but no one has heretofore contemplated such adjustment as a means for readily varying the speed of the motor during the operation thereof, and no one has ever contemplated the utilization of the variable compression of the starting resistance columns as a means for procurin variation of the normal running speed of a motor with which the device is associated, and I therefore consider the independent utilization of this means of control to be a salient feature of my invention. i

It will also be noted that I have provided an exceedin ly efiective mounting for the resistance co umns 11, by passing said columns through snugly fitted openings of the upper and lower insulating slabs 10 and suspending said columns by the engagement of their upper end projections 14 on the upper slab 10, whereby said columns may be readily assembled or disassembled in the device. These insulating slabs 10 also carry binding posts 48 for effecting the connections of the circuit Wires with the resistance columns, the slabs thus serving the function of insulating the binding post 40 and of affording insulation for the resistance columns in addition to the normal insulation which is afforded by the linings of their casings 11.

While I have shown and described a preferred embodiment of my invention, it will be understood that various changes and modifications of structure may be-employed to meet differing conditions of use and manufacture without departing in any manner from the spirit of my invention.

What is claimed is: l

1. A controlling device of the class described, comprising a compression resistance medium, means movable to compress the resistance medium, and adjustable means independent of said. first mentioned means for determining the pressure imparted to said resistance medium by the movable means, the adjustment of said independent means being undisturbed by manipulation of said movable means from either compressing position or non-compressing position.

2. A controlling device of the class described, comprising a compressible resistance medium, a normally open circuit including said medium, means for imparting gradually increasing pressure to said medium to a predeterminedlimit, means operable at the beginning and during actuation of the first named means for closing said circuit and for maintaining said circuit closed during the continuance of said compression, and means operable independently of the first named means during the closure of said circuit, and subsequently to the compression of the medium to said predetermined limit, for varying the compression of said medium.

3.. A controlling device of the class described, comprising a compressible medium, a normally open circuit including said medium, means for imparting gradually increasing pressure to said medium to a. predetermined limit, means operable at the beginning and during actuation of the first named means for closing said circuit and for maintaining said circuit closed during the continuance of said compression, means operable independently of the first named means during the closure of said circuit, and subsequently to the compression of the medium to said predetermined limit, for varying the compression of said medium, and

means for releasably holding the pressure imparting means in position with the resistance medium under compression.

4. A controlling device of the class described, comprisin a plurality of compres sible resistance co umns, a single plate engageable with the heads of all of said columns to compress the columns, a tension rod movable transversely of the plate, means for moving said tension rod to transmit pressure .to the plate, and a manual grip member rotatable on the said tension rod and operable to adjust the pressure transmitted to the plate by the rod.

5. A controlling device of the class described comprising a plurality of compressible resistance columns, a plate engageable with the heads of said columns to com-' press the columns, a cup-shaped depression in. the pressureplate located between the ends of the columns, a tension rod passed through said cup-shaped depression, a spring within the cup-shaped depression, a member on the tension rod for compressing said spring and transmitting pressure to the plate; and means for moving the tension rod.

6. A controlling device of the class described comprising a plurality of upstanding compressible resistance columns, a plate disposed over and engageable with the heads of said columns to compress the columns, a tension rod connected with the plate, posts loosely passed through the plate, springs on said posts engaging the plate to relieve pressure of the same on the columns, and means for moving the tension rod toftransmit tension through the plate against the action of said springs.

7. A controlling device of the class described comprising a. plurality of upstanding compressible resistance columns, a. plate engageable with the heads of said columns to compress the columns, a cup-shaped depression in said plate, a tension rod passed through the depression, a spring on said rod Within the depression, posts loosely passed through the plate, springs on said posts engaging the plate to relieve pressure of the same on the columns, means for moving the tension rod to transmit tension through the plate against the action of said springs.

8. A controlling device of the class described including a casing, transverse" members of insulating material carried thereby and provided with registering openings, a compressible resistance column slidable through the openings and having its end portions mounted therein, a stop projection on said column engageable with one of the said members, and means for exerting pressure against the column in the direction of the engagement of its stop projection with the said member.

9. A controlling device of the class described including a casing, transverse memcompressible bers of insulating material carried thereby and provided with registering openings, a resistance column slidable through the openings and having its end portions mounted therein, means carried by said insulating members for procuring electrical connections with the ends of the column, a stop projection on said column engageable with one of the said members, and means for exerting pressure against the column in the direction of the engagement of its stop projection with the said member.

10. A controlling device of the class described including a casing having sides and ends, plates secured transversely in the casing adjacent the ends thereof, slabs of insulatin material carried by said plates and provided with registering openings, a compressible resistance column slidable through the openings and having its end portions mounted therein means carried by said insulating slabs for procuring electrical connections with the ends of the column, a stop projection on said column engageable wit-h one of the said members, and means for exerting pressure against the column in the direction of the engagement of its stop projection with the said member.

11. A controlling device of the class described including acasing, a compressible resistance column in the casing, a shaft journaled in the casing transversely of the resistance column, means operable upon rotation of the shaft for compressing the column, a pair of arcuate contacts carried on the shaft, stationary contacts engageable by said arcuate contacts, and means operable upon energizing said circuit for holding the shaft against rotation.

12. A controlling device of the class described including a casing, a compressible resistance column in the casing, a shaft journaled in the casing transversely of the resistance column, a. tension rod in the casing operable by rotation of said shaft, a grip member threaded on the tension rod for transmitting tension to the column, said grip member extending outwardly of the casing for providing an independent adjustment of the compression of said column, means operable upon rotation of the shaft for compressing the column, a pair of arcuate contacts carried on the shaft,stationary contacts engageable by said arcuate contacts upon rotation of the shaft, a circuit including said contacts, and means operable upon energizing said circuit for holding the shaft against rotation.

In testimony that I claim the foregoing I have hereunto set my hand at Milwaukee, in the county of Milwaukee and State of Wisconsin.

GUSTAV O. WILMS. 

